Sealing device



H. F. GREINER May 2, 1950 SEALING DEVICE Filed April 4, 1947 INVENTORbfi/H520 @PN/Vf@ w M ATTORNE@ Patented May 2, 1950 SEALING DEVICE HaroldF. Greiner, Geneva, N. Y., assignor to The Garlock Packing Company,Palmyra, N. Y., a corporation of New York Application April 4, 1947,Serial No. 739,326

(Cl. :BSG- 11) 5 Claims.

This invention relates to improvements in sealing devices for effectinga seal against the passage of iiuid or of dust, dirt or other foreignmatter between relatively movable machine elements as, for example,between a rotating shaft and a machine casing within which the shaft ismounted. More particularly, the invention relates to such sealingdevices in which the sealing effect between such relatively moving partsoccurs at radially extending surfaces of said parts or of elementsassociated therewith.

Where the sealing effect is at radially extending surfaces it has beenfound that the sealing elements may quite conveniently be urged axiallytogether into sealing engagement, usually by the use of one or moresprings. The springs ordinarily hold the sealing elements together sothat the sealing effect is maintained despite wear which may occur uponone or both sealing surfaces. Also, the spring or springs may besumciently stressed to render the seal effective where material uidpressure is present in the machine structure as would be the oase wherethe sealing device is employed in sealing the shaft of a pump.

Most sealing devices of this type heretofore developed have been quitecomplicated and in most cases were of a character which required theparts thereof to be assembled on the job. Thus there was not only thenuisance of assembly on the job, but also the possibility that aninexpert worker might assemble the parts incorrectly and thus defeat thepurpose of the device.

An important object of the present invention is the provision of aunitary radial sealing device which may be completely assembled in themanufacture thereof.

Another important object is the provision of such a sealing device whichis very simple and has relatively few parts, and in which the parts areeasily assembled in the process of manufacture so that the device may bevery economically produced.

Another important object is the provision of such a sealing device witha resilient element that may ex to a substantial extent without howeversetting up any substantial deformation stresses therein. Thus, althoughthere may be substantial flexing of the resilient element, neverthelessthe internal stresses set up therein are so slight that the flexing ofthe element does not tend to cause it to break down in service.

Another important object is the provision of such a sealing device whichis relatively small in radial sectional diameter so that it may be 56disposed in a relatively small annular space provided therefor in amachine assembly.

Another important object is the provision of such a. sealing device inwhich certain flexible portions are arranged with opposed surfacessubjected to substantially balanced pressures to prevent collapse ofsuch parts under substantiai pressure conditions.

Another important object is the provision ci such a sealing device inwhich a distensible nexible web is backed up by a portion of asubstantially non-nexible element to prevent excessive distension of theweb.

The foregoing and other objects are accomplished by the presentinvention which, for illustrative purposes only, is shown in a singleembodiment in the accompanying drawings in which:

Figure l is a central axial sectional view oi a sealing device accordingto the present invention, and

Fig. 2 is an axial sectional view of said derice in association with amachine casing and a shaft extending through said casing, the shaftbeing shown in elevation in order to clarify the drawings..

As illustrated, the present device may comprise a sleeve-like diaphragmI, preferably formed of relatively soft flexible rubber or syntheticrubber or other flexible rubber-like material (hereinafter referred tofor convenience merely as rubber), a sealing ring I2 which may be ofsuitable material as, for example, a graphiteimpregnatedself-lubricating metal, a helical spring i 3 and a washer I 4, all heldin assembled relationship within a shell I5 which preferably is formedof suitable metal.

The assembled device is shown in Fig. 1 unassociated with any machineelements. From this figure, it may be seen that the spring I3 is undercompression between the inner left end Ilia of the shell I5 and a radialange I Ia of the dia phragm II, the Washer Il being interposed betweenthe adjacent end of the spring I3 and the flange Ila in order to providea suitable seat for said spring. The radial flange IIa preferably isthickened somewhat and provided with an angularly annular bead IIb whichfits within a. complementally shaped annular recess I2a of the sealingring I2.

Under the described arrangement the compression of the spring I3, actingthrough the washer I4 and the radial flange IIa of the diaphragm II,urges the sealing ring I2 toward the right to its extreme position, asshown in Fig. 1,

to which position it is limited by an in-turned annular ange Ib formedon the right end of the shell I5 to engage an annular shoulder I2b ofthe sealing ring I2.

The diaphragm II preferably has integral thick and thin sleeve portionsllc, and Ild respectively, at opposite ends thereof and ordinarily theinitial inner diameter of these sleeve portions would be slightly lessthan the diameter of a shaft I6 for which the device is designed to beused. Thus, when the device is slid forcibly onto the shaft, thediaphragm grips the latter firmly and thereby is restrained againsteither rotational or axial movement relatively thereto and also effectsa fixed seal therewith. This gripping effect is enhanced by reason ofthe fact that the left end of the shell I5 is turned in and back uponitself to form an internal axial flange I5c which is firmly embedded inthe thickened sleeve portion I I c of the diaphragm.

The described arrangement is such that when the device is forcibly slidonto the shaft the diaphragm portion I Ic is squeezed between the shaftand the shell flange I5c so thatboth the diaphragm II and the shell I5in normal use are prevented from sliding along the shaft and are bothconstrained to "rotate therewith.

In many installations, reliance would not be placed entirely upon thefrictional engagement of the diaphragm II and the shaft to preventmovement of the device along the latter, for, as shown in Fig. 2, thethickened portion IIc of the diaphragm may be positioned against ashoulder IBa formed upon the shaft or a collar, snap ring, impeller hubor the like, thereby positively restricting the device against leftwardmovement relatively thereto.

In the assembly of the device in a machine,

the shaft I6, after the present sealing device is positioned thereon, ismoved rightwardly relatively to a housing I1 to bring a radial outerface I2c of the sealing ring I2 into sealing engagement with anopposedradial sealing face I'Ia of the housing I1. After initial contact of thesealing surfaces, the shaft is moved somewhat more toward the rightrelatively to the housing I 1, thereby pressing the sealing ring I2further into the shell I5 to move the shouldered portion |2b entirelyclear of engagement with the annular ange I 5b of the shell. In thiscondition, the connecting portion IIe extends into a concave counterboreI2e in the sealing ring I2 with a relatively small clearance Withrespect to the surface of said counterbore; also the force of the springI3 becomes operative to somewhat yieldingly urge the sealing surface I2cinto running seal engagement with the surface Ila and to maintain suchengagement despite possible limited endwise movement of the shaftrelatively to the housing. Although the parts of the present sealingdevice are substantially constrained to rotate together because of theirfrictional inter-engagement, nevertheless means for positively assuringsuch rotation, particularly with respect to the sealing ring I2,preferably are provided in the form of an axially extending groove I2dformed in the outer face of the shouldered portion I2b of the sealingring and a dimple or detent I5d in the shell I'5 which detent extendsinto the groove I2C to prevent material relative rotation between theshell and the sealing ring while nevertheless permitting relative axialmovement of the two.

It may be observed by comparing Figs. 1 and 2 that when the sealing ringI2 is pressed further into the shell I5' as when the device is assembledin a machine, the sleeve portions IIc and Hd of the diaphragm for themost part are unaffected, while the radial flange IIa of the diaphragmis pushed axially leftwardly relatively to the shell. During the lattermovement a channel shaped connecting portion IIe of the diaphragmpursues a slight rolling movement which slightly shortens the sleeveportion Ild and slightly lengthens axially the connecting portion IIeadjacent to its juncture with the radial flange Ila.

In this rolling movement the diaphragm II rolls away from the shaft I6to some extent and to some extent back upon itself. The internaldiameter of the radial flange IIa is sumciently greater than the outerdiameter of the sleeve portion IId that these parts clear each other sothat such rolling movement will be substantially unrestrained.

The diaphragm II may advantageously be molded to its shape as shown inFig. 2 so that, in operation, the connecting portion IIe normally is notunder any substantial internal stress and any back and forth rolling ofsaid portion, caused by end-play of the shaft, would be relativelyslight and would involve only slight and harmless internal stressing ofthe portion IIe. Even if the diaphragm were molded in its shape as shownin Fig. 1, the rolling movement in operation would not be sufficient tocause rupture of the diaphragm. The capacity of the diaphragm to resistrupture from repeated rolling movements lies in a great measure in thefact that even a substantial rolling movement accompanying substantialaxial movement of the sealing ring I2 within the shell causes onlynegligible cross sectional deformation of the web constituting theconnecting portion I le of the diaphragm and only minor internalstresses therein which are so slight as not to cause rupture of thediaphragm even under substantially continuous back and forth rolling ofthe diaphragm during long periods of machine operation.

Optionally, the axial flange I-5c of the shell may be bonded to thethickened sleeve portion I Ic of the diaphragm. The diaphragm II, also,may be bonded to the sealing ring I2, if desired.

As thus far described, it will be understood that this device willfunction effectively under low pressure conditions, but it is alsoeffective at relatively high pressures. In structures wherein highpressure is present, the high pressure area is the area within theconnecting portion IIe and partially defined by the inner and outerperipheries of the flange IIa. Thus the effect of high pressure on saidperipheries is substantially balanced, thereby avoiding any radialcollapsing or deformation of the flange Ila either inwardly oroutwardly. Although the tongue and groove arrangement I Ib, I 2a, aidedby the spring I3, would effectively prevent such deformation under lowpressure conditions, it alone, would be unreliable for that purposeunder high pressure conditions. In this device the radially directedforce of the high pressure on the flange I Ia is substantially inbalance and the high pressure is also effective, in addition to thespring I3, to press the ilange IIa rightwardly, as viewed in thedrawings, thereby rendering the mentioned tongue and groove moreeffective for preventing such collapsing of the said ange. Any tendencyof the connecting portion IIe to be distended by high pressuretherewithin is positively limited by the fact that the portion I le isdisposed within the concave counterbore |2e of the sealing ring I2. Thiscounterbore, of course, is large enough to permit the portion Ile toroll within said counterbore during the abovedescribed use of thedevice, and yet, the surface of said counterbore is sufficiently closeto the portion Ile that it positively limits the distension of thatportion so that it will not be damaged by the pressure.

From the foregoing it should be obvious that a sealing device accordingto the present invention is very durable and may be a unitary structureconsisting of very few parts. The device is easily assembled in beingmanufactured and it is easily incorporated into a machine withoutinvolving the possibility of parts being improperly assembled by anunskilled workman. Also, the parts are so designed that the device maybe disposed within a space of relatively small radial dimensions as isprovided in some machines.

Although only one embodiment of the invention is disclosed in thedrawings and described in the present specification, it should beapparent, nevertheless, that the present inventive concept could beemployed in various other ways Without, however, departing from thespirit of the invention as defined in the accompanying claims.

What I claim is:

1. The combination in a sealing device comprising a sleeve-like rubberdiaphragm having a marginal ring at one end and a U-shaped annular webflexibly supporting said marginal ring with the convex surface of the Ufacing in the same direction as said one end, a sealing ring in sealingengagement with one side of said marginal ring and having an annularconcave portion in axially opposed relationship to said convex surfacefor receiving and supporting said web against excessive distension, andan outer shell of strong rigid material having a cylindrical outerportion surrounding both a portion of the diaphragm and a. portion ofthe sealing ring, a web extending radially inwardly from one end of saidshells outer cylindrical portion, an inner cylindrical flange extendingaxially within said outer cylindrical portion from the inner margin ofsaid web and being in substantially non-slipping engagement with saidsleeve, and an inturned annular ange on the other end of the shellsouter cylindrical portion extending into axial alignment with a portionof said sealing ring whereby to limit the latters axial movement awayfrom said diaphragm.

2. A sealing device for effecting a seal between relatively rotatableouter and inner machine elements comprising a rubber diaphragm having acylindrical mounting portion adapted to llt tightly upon a cylindricalouter surface of said inner element, a radially outwardly extendingannular U-shaped flexible web one extremity of which is integral withthe inner end of said mounting portion, and anannular sealing portiondirectly integral with said web at the latter's other extremity and oflarger inner diameter than the outer diameter of said inner end` of themounting portion and capable of axial telescoping movement relatively tosaid mounting portion. a sealing ring having an annular inner sidesurface in sealing engagement with an opposed annular outer side surfaceof said annular sealing portion, a shell of relatively strong rigidmaterial having a cylindrical portion surrounding both the diaphragm andthe sealing ring but leaving a portion of the latter with an outerradial sealing surface thereon protruding beyond the adjacent end of theshell, the latter partially defining an annular space between themounting portion of the diaphragm and the said cylindrical portion ofthe shell, the latter having a first inturned portion at one end infixed engagement with the diaphragms mounting portion and a secondinturned portion at its other end coacting with said sealing ring tolimit the latters movement axially outwardly of the shell, and resilientmeans disposed within said annular space and coacting with the shellssaid first inturned portion and with said annular sealing portion of thediaphragm for yieldably urging the latter and the sealing ring towardengagement of the latter with said second inturned portion of the shell.

3. A sealing device according to claim' 2, the said rst inturned portionof the shell comprising a radial web defining one end of said annularspace and the said resilient means comprising a coil spring encirclingsaid mounting portion disposed within said space and compressed betweensaid web and the said peripheral ring.A

4. A sealing device according to claim 2, the said U-shaped web beingdirectly connected with the annular sealing portion and with theadjacent inner end of the mounting portion of the diaphragm, the saidU-shaped web being of substantially the same thickness as said inner endof the mounting portion and constituting an arcuate continuationthereof, the said U-shaped web and said inner end of the mountingportion being rollable about an annular axis line within the U in thepresence of axial movement of the annular sealing portion.

5. A sealing device according to claim 2, the convex surface of theannular U-shaped web facing the sealing ring and the latter having anopposed concave portion for receiving said web therewithin andsupporting said web against excessive distension.

HAROLD F. GREINER.

REFERENCES CITED The following references are of record in the ille ofthis patent:

UNITED STATES PATENTS Certificate of Correction Patent No. 2,506,447 May2, 1950 HAROLD F. GREINER It is hereby certified that errors appear inthe printed specification of the above numbered patent requiringcorrection as follows:

Column 2, lines 47 and 48, for the Word singularly read angular; column5, line 61, after Wit insert and a continuation of;

and that the said Letters Patent should be reed with these correctionstherein that the same may conform to the record of the case in thePatent Office.

Signed and sealed this 22nd day of August, A. D. 1950.

THOMAS F. MURPHY,

Assistant Commissioner of Patents,

Certificate of Correction Patent No. 2,506,447 May 2, 1950 HAROLD F.GREINER It is hereby certiied that errors appear in the printedspecification of the above numbered patent requiring correction asfollows:

Column 2, lines 47 and 48, for the word angularly read angular; column5, line 61, after with insert and a continuation of;

and that the said Letters Patent should be read with these correctionstherein that the same may conform to the record of the oase in thePatent Office.

Signed and sealed this 22nd day of August, A. D. 1950.

THOMAS F. MURPHY,

Assistant Commissioner of Patents.

